diff mbox

[V8,2/2] irqchip: gicv2m: Add supports for ARM GICv2m MSI(-X)

Message ID 1411230698-8081-3-git-send-email-suravee.suthikulpanit@amd.com (mailing list archive)
State New, archived
Headers show

Commit Message

Suravee Suthikulpanit Sept. 20, 2014, 4:31 p.m. UTC
From: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>

ARM GICv2m specification extends GICv2 to support MSI(-X) with
a new set of register frame. This patch introduces support for
the non-secure GICv2m register frame. Currently, GICV2m is available
in certain version of GIC-400.

The patch introduces a new property in ARM gic binding, the v2m subnode.
It is optional.

Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Acked-by: Marc Zyngier <Marc.Zyngier@arm.com>
Cc: Mark Rutland <Mark.Rutland@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Catalin Marinas <Catalin.Marinas@arm.com>
Cc: Will Deacon <Will.Deacon@arm.com>
---
 Documentation/devicetree/bindings/arm/gic.txt |  55 ++++
 arch/arm64/Kconfig                            |   1 +
 drivers/irqchip/Kconfig                       |   5 +
 drivers/irqchip/Makefile                      |   1 +
 drivers/irqchip/irq-gic-common.c              |  12 +
 drivers/irqchip/irq-gic-common.h              |   4 +
 drivers/irqchip/irq-gic-v2m.c                 | 356 ++++++++++++++++++++++++++
 drivers/irqchip/irq-gic.c                     |  82 +++---
 drivers/irqchip/irq-gic.h                     |  54 ++++
 9 files changed, 540 insertions(+), 30 deletions(-)
 create mode 100644 drivers/irqchip/irq-gic-v2m.c
 create mode 100644 drivers/irqchip/irq-gic.h

Comments

Mark Rutland Sept. 22, 2014, 5:37 p.m. UTC | #1
Hi Suravee,

This looks good, I just have a few fixups that would be nice to apply
below.

On Sat, Sep 20, 2014 at 05:31:38PM +0100, suravee.suthikulpanit@amd.com wrote:
> From: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
> 
> ARM GICv2m specification extends GICv2 to support MSI(-X) with
> a new set of register frame. This patch introduces support for
> the non-secure GICv2m register frame. Currently, GICV2m is available
> in certain version of GIC-400.
> 
> The patch introduces a new property in ARM gic binding, the v2m subnode.
> It is optional.
> 
> Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
> Acked-by: Marc Zyngier <Marc.Zyngier@arm.com>
> Cc: Mark Rutland <Mark.Rutland@arm.com>
> Cc: Jason Cooper <jason@lakedaemon.net>
> Cc: Catalin Marinas <Catalin.Marinas@arm.com>
> Cc: Will Deacon <Will.Deacon@arm.com>
> ---
>  Documentation/devicetree/bindings/arm/gic.txt |  55 ++++
>  arch/arm64/Kconfig                            |   1 +
>  drivers/irqchip/Kconfig                       |   5 +
>  drivers/irqchip/Makefile                      |   1 +
>  drivers/irqchip/irq-gic-common.c              |  12 +
>  drivers/irqchip/irq-gic-common.h              |   4 +
>  drivers/irqchip/irq-gic-v2m.c                 | 356 ++++++++++++++++++++++++++
>  drivers/irqchip/irq-gic.c                     |  82 +++---
>  drivers/irqchip/irq-gic.h                     |  54 ++++
>  9 files changed, 540 insertions(+), 30 deletions(-)
>  create mode 100644 drivers/irqchip/irq-gic-v2m.c
>  create mode 100644 drivers/irqchip/irq-gic.h
> 
> diff --git a/Documentation/devicetree/bindings/arm/gic.txt b/Documentation/devicetree/bindings/arm/gic.txt
> index c7d2fa1..38b2156 100644
> --- a/Documentation/devicetree/bindings/arm/gic.txt
> +++ b/Documentation/devicetree/bindings/arm/gic.txt
> @@ -96,3 +96,58 @@ Example:
>                       <0x2c006000 0x2000>;
>                 interrupts = <1 9 0xf04>;
>         };
> +
> +
> +* GICv2m extension for MSI/MSI-x support (Optional)
> +
> +Certain revision of GIC-400 supports MSI/MSI-x via V2M register frame.
> +This is enabled by specifying v2m sub-node.

It looks like this was missed when the binding was updated for multiple
frames, so:

s/revision/revisions/
s/frame/frame(s)/
s/sub-node/sub-node(s)/

> +
> +Required properties:
> +
> +- compatible        : The value here should be "arm,gic-v2m-frame".

- compatible: should contain "arm,gic-v2m-frame".

> +
> +- msi-controller    : Identifies the node as an MSI controller.
> +
> +- reg               : GICv2m MSI interface register base and size
> +
> +Optional properties:
> +
> +- arm,msi-base-spi  : Specify base SPI the MSI frame.
> +                      The SPI base value can be from 32 to 1019.
> +
> +- arm,msi-num-spi   : Returns the number of contiguous SPIs assigned
> +                     to the frame.
> +
> +Note: "arm,msi-base-spi" and "arm,msi-num-spi" are used mainly for
> +       providing HW workaround in the case where the MSI_TYPER register
> +       is corrupted.

s/num-spi/num-spis/ please

Can we get rid of the note and reword this like:

- arm,msi-base-spi: When the MSI_TYPER register contains an incorrect
                    value, this property should contain the SPI base of
		    the MSI frame, overriding the HW value.

- arm,msi-num-spis: When the MSI_TYPER register contains an incorrect
                    value, this property should contain the number of
                    SPIs assigned to the frame, overriding the HW value.

I realise it's a little redundant, but it's very easy to miss usage
constraints in notes.

With that, for the binding:

Acked-by: Mark Rutland <mark.rutland@arm.com>

Mark.
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/arm/gic.txt b/Documentation/devicetree/bindings/arm/gic.txt
index c7d2fa1..38b2156 100644
--- a/Documentation/devicetree/bindings/arm/gic.txt
+++ b/Documentation/devicetree/bindings/arm/gic.txt
@@ -96,3 +96,58 @@  Example:
 		      <0x2c006000 0x2000>;
 		interrupts = <1 9 0xf04>;
 	};
+
+
+* GICv2m extension for MSI/MSI-x support (Optional)
+
+Certain revision of GIC-400 supports MSI/MSI-x via V2M register frame.
+This is enabled by specifying v2m sub-node.
+
+Required properties:
+
+- compatible        : The value here should be "arm,gic-v2m-frame".
+
+- msi-controller    : Identifies the node as an MSI controller.
+
+- reg               : GICv2m MSI interface register base and size
+
+Optional properties:
+
+- arm,msi-base-spi  : Specify base SPI the MSI frame.
+                      The SPI base value can be from 32 to 1019.
+
+- arm,msi-num-spi   : Returns the number of contiguous SPIs assigned
+		      to the frame.
+
+Note: "arm,msi-base-spi" and "arm,msi-num-spi" are used mainly for
+       providing HW workaround in the case where the MSI_TYPER register
+       is corrupted.
+
+Example:
+
+	interrupt-controller@e1101000 {
+		compatible = "arm,gic-400";
+		#interrupt-cells = <3>;
+		#address-cells = <2>;
+		#size-cells = <2>;
+		interrupt-controller;
+		interrupts = <1 8 0xf04>;
+		ranges = <0 0 0 0xe1100000 0 0x100000>;
+		reg = <0x0 0xe1110000 0 0x01000>,
+		      <0x0 0xe112f000 0 0x02000>,
+		      <0x0 0xe1140000 0 0x10000>,
+		      <0x0 0xe1160000 0 0x10000>;
+		v2m0: v2m@0x8000 {
+			compatible = "arm,gic-v2m-frame";
+			msi-controller;
+			reg = <0x0 0x80000 0 0x1000>;
+		};
+
+		....
+
+		v2mN: v2m@0x9000 {
+			compatible = "arm,gic-v2m-frame";
+			msi-controller;
+			reg = <0x0 0x90000 0 0x1000>;
+		};
+	};
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index fd4e81a..83d5556 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -12,6 +12,7 @@  config ARM64
 	select ARM_ARCH_TIMER
 	select ARM_GIC
 	select AUDIT_ARCH_COMPAT_GENERIC
+	select ARM_GIC_V2M
 	select ARM_GIC_V3
 	select BUILDTIME_EXTABLE_SORT
 	select CLONE_BACKWARDS
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index b8632bf..61d18d9 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -7,6 +7,11 @@  config ARM_GIC
 	select IRQ_DOMAIN
 	select MULTI_IRQ_HANDLER
 
+config ARM_GIC_V2M
+	bool
+	depends on ARM_GIC
+	depends on PCI && PCI_MSI
+
 config GIC_NON_BANKED
 	bool
 
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 73052ba..3bda951 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -17,6 +17,7 @@  obj-$(CONFIG_ARCH_SUNXI)		+= irq-sun4i.o
 obj-$(CONFIG_ARCH_SUNXI)		+= irq-sunxi-nmi.o
 obj-$(CONFIG_ARCH_SPEAR3XX)		+= spear-shirq.o
 obj-$(CONFIG_ARM_GIC)			+= irq-gic.o irq-gic-common.o
+obj-$(CONFIG_ARM_GIC_V2M)		+= irq-gic-v2m.o
 obj-$(CONFIG_ARM_GIC_V3)		+= irq-gic-v3.o irq-gic-common.o
 obj-$(CONFIG_ARM_NVIC)			+= irq-nvic.o
 obj-$(CONFIG_ARM_VIC)			+= irq-vic.o
diff --git a/drivers/irqchip/irq-gic-common.c b/drivers/irqchip/irq-gic-common.c
index 60ac704..4b8cff2 100644
--- a/drivers/irqchip/irq-gic-common.c
+++ b/drivers/irqchip/irq-gic-common.c
@@ -113,3 +113,15 @@  void gic_cpu_config(void __iomem *base, void (*sync_access)(void))
 	if (sync_access)
 		sync_access();
 }
+
+int gic_msi_get_vec_count(struct pci_dev *pdev, struct msi_desc *desc)
+{
+	int ret = -EINVAL;
+#ifdef CONFIG_PCI_MSI
+	if (desc->msi_attrib.is_msix)
+		ret = pci_msix_vec_count(pdev);
+	else
+		ret = pci_msi_vec_count(pdev);
+#endif
+	return ret;
+}
diff --git a/drivers/irqchip/irq-gic-common.h b/drivers/irqchip/irq-gic-common.h
index b41f024..95049e5 100644
--- a/drivers/irqchip/irq-gic-common.h
+++ b/drivers/irqchip/irq-gic-common.h
@@ -19,6 +19,8 @@ 
 
 #include <linux/of.h>
 #include <linux/irqdomain.h>
+#include <linux/pci.h>
+#include <linux/msi.h>
 
 void gic_configure_irq(unsigned int irq, unsigned int type,
                        void __iomem *base, void (*sync_access)(void));
@@ -26,4 +28,6 @@  void gic_dist_config(void __iomem *base, int gic_irqs,
 		     void (*sync_access)(void));
 void gic_cpu_config(void __iomem *base, void (*sync_access)(void));
 
+int gic_msi_get_vec_count(struct pci_dev *pdev, struct msi_desc *desc);
+
 #endif /* _IRQ_GIC_COMMON_H */
diff --git a/drivers/irqchip/irq-gic-v2m.c b/drivers/irqchip/irq-gic-v2m.c
new file mode 100644
index 0000000..554b1b1
--- /dev/null
+++ b/drivers/irqchip/irq-gic-v2m.c
@@ -0,0 +1,356 @@ 
+/*
+ * ARM GIC v2m MSI(-X) support
+ * Support for Message Signaled Interrupts for systems that
+ * implement ARM Generic Interrupt Controller: GICv2m.
+ *
+ * Copyright (C) 2014 Advanced Micro Devices, Inc.
+ * Authors: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
+ *          Harish Kasiviswanathan <harish.kasiviswanathan@amd.com>
+ *          Brandon Anderson <brandon.anderson@amd.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#define pr_fmt(fmt) "GICv2m: " fmt
+
+#include <linux/bitmap.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "irqchip.h"
+#include "irq-gic.h"
+#include "irq-gic-common.h"
+
+/*
+* MSI_TYPER:
+*     [31:26] Reserved
+*     [25:16] lowest SPI assigned to MSI
+*     [15:10] Reserved
+*     [9:0]   Numer of SPIs assigned to MSI
+*/
+#define V2M_MSI_TYPER			0x008
+#define V2M_MSI_TYPER_BASE_SHIFT	16
+#define V2M_MSI_TYPER_BASE_MASK		0x3FF
+#define V2M_MSI_TYPER_NUM_MASK		0x3FF
+#define V2M_MSI_SETSPI_NS		0x040
+#define V2M_MIN_SPI			32
+#define V2M_MAX_SPI			1019
+
+#define V2M_MSI_TYPER_BASE_SPI(x)	\
+		(((x) >> V2M_MSI_TYPER_BASE_SHIFT) & V2M_MSI_TYPER_BASE_MASK)
+
+#define V2M_MSI_TYPER_NUM_SPI(x)	((x) & V2M_MSI_TYPER_NUM_MASK)
+
+/*
+ * alloc_msi_irq - Allocate MSIs from available MSI bitmap.
+ * @data: Pointer to v2m_data
+ * @nvec: Number of interrupts to allocate
+ * @irq: Pointer to the allocated irq
+ *
+ * Allocates interrupts only if the contiguous range of MSIs
+ * with specified nvec are available. Otherwise return the number
+ * of available interrupts. If none are available, then returns -ENOENT.
+ */
+static int alloc_msi_irq(struct v2m_data *data, int nvec, int *irq)
+{
+	int size = data->nr_spis;
+	int next = size, i = nvec, ret;
+
+	/* We should never allocate more than available nr_spis */
+	if (i >= size)
+		i = size;
+
+	spin_lock(&data->msi_cnt_lock);
+
+	for (; i > 0; i--) {
+		next = bitmap_find_next_zero_area(data->bm,
+					size, 0, i, 0);
+		if (next < size)
+			break;
+	}
+
+	if (i != nvec) {
+		ret = i ? : -ENOENT;
+	} else {
+		bitmap_set(data->bm, next, nvec);
+		*irq = data->spi_start + next;
+		ret = 0;
+	}
+
+	spin_unlock(&data->msi_cnt_lock);
+
+	return ret;
+}
+
+static void gicv2m_teardown_msi_irq(struct msi_chip *chip, unsigned int irq)
+{
+	int pos;
+	struct v2m_data *data = container_of(chip, struct v2m_data, msi_chip);
+
+	spin_lock(&data->msi_cnt_lock);
+
+	pos = irq - data->spi_start;
+	if (pos >= 0 && pos < data->nr_spis)
+		bitmap_clear(data->bm, pos, 1);
+
+	spin_unlock(&data->msi_cnt_lock);
+}
+
+bool gicv2m_check_msi_range(struct gic_chip_data *gic, irq_hw_number_t hw)
+{
+	struct v2m_data *v2m = NULL;
+
+	list_for_each_entry(v2m, &gic->v2m_list, list) {
+		if (hw >= v2m->spi_start &&
+		    hw <  v2m->spi_start + v2m->nr_spis)
+			return true;
+	}
+	return false;
+}
+
+static int gicv2m_setup_msi_irq(struct msi_chip *chip,
+				struct pci_dev *pdev,
+				struct msi_desc *desc)
+{
+	int i, irq, nvec, avail;
+	struct msi_msg msg;
+	phys_addr_t addr;
+	struct msi_desc *entry;
+	struct v2m_data *data = container_of(chip, struct v2m_data, msi_chip);
+
+	if (!desc) {
+		dev_err(&pdev->dev,
+			"MSI setup failed. Invalid msi descriptor\n");
+		return -EINVAL;
+	}
+
+	if (desc->msi_attrib.is_msix) {
+		/**
+		 * For MSIx:
+		 * We allocate one irq at a time
+		 */
+		avail = alloc_msi_irq(data, 1, &irq);
+		if (avail != 0) {
+			dev_err(&pdev->dev,
+				"MSI setup failed. Cannnot allocate IRQ\n");
+			return -ENOSPC;
+		}
+
+		irq_set_chip_data(irq, chip);
+		irq_set_msi_desc(irq, desc);
+		irq_set_irq_type(irq, IRQ_TYPE_EDGE_RISING);
+	} else {
+		/**
+		 * For MSI and Multi-MSI:
+		 * All requested irqs are allocated and setup at
+		 * once. Subsequent calls to this function would simply return
+		 * success. This is to avoid having to implement a separate
+		 * function for setting up multiple irqs.
+		 */
+		BUG_ON(list_empty(&pdev->msi_list));
+		WARN_ON(!list_is_singular(&pdev->msi_list));
+
+		nvec = gic_msi_get_vec_count(pdev, desc);
+		if (WARN_ON(nvec <= 0))
+			return nvec;
+
+		entry = list_first_entry(&pdev->msi_list,
+					 struct msi_desc, list);
+
+		if ((nvec > 1) && (entry->msi_attrib.multiple))
+			return 0;
+
+		avail = alloc_msi_irq(data, nvec, &irq);
+		if (avail != 0) {
+			dev_err(&pdev->dev,
+				"Failed to allocate %d irqs.\n", nvec);
+			return avail;
+		}
+
+		if (nvec > 1) {
+			/* Set lowest of the new interrupts assigned
+			 * to the PCI device
+			 */
+			entry->nvec_used = nvec;
+			entry->msi_attrib.multiple = ilog2(
+						__roundup_pow_of_two(nvec));
+		}
+
+		for (i = 0; i < nvec; i++) {
+			irq_set_chip_data(irq+i, chip);
+			if (irq_set_msi_desc_off(irq, i, entry)) {
+				dev_err(&pdev->dev,
+					"Failed to set up MSI irq %d\n",
+					(irq+i));
+				return -EINVAL;
+			}
+
+			irq_set_irq_type((irq+i), IRQ_TYPE_EDGE_RISING);
+		}
+	}
+
+	addr = data->res.start + V2M_MSI_SETSPI_NS;
+	msg.address_hi = (u32)(addr >> 32);
+	msg.address_lo = (u32)(addr);
+	msg.data = irq;
+	write_msi_msg(irq, &msg);
+
+	return 0;
+}
+
+static void gicv2m_mask_irq(struct irq_data *d)
+{
+	gic_mask_irq(d);
+	if (d->msi_desc)
+		mask_msi_irq(d);
+}
+
+static void gicv2m_unmask_irq(struct irq_data *d)
+{
+	gic_unmask_irq(d);
+	if (d->msi_desc)
+		unmask_msi_irq(d);
+}
+
+static bool is_msi_spi_valid(u32 base, u32 num)
+{
+	if (base < V2M_MIN_SPI) {
+		pr_err("Invalid MSI base SPI (base:%u)\n", base);
+		return false;
+	}
+
+	if ((num == 0) || (base + num > V2M_MAX_SPI)) {
+		pr_err("Number of SPIs (%u) exceed maximum (%u)\n",
+		       num, V2M_MAX_SPI - V2M_MIN_SPI + 1);
+		return false;
+	}
+
+	return true;
+}
+
+static int __init
+gicv2m_init_one(struct device_node *node, struct v2m_data **v,
+		struct gic_chip_data *gic)
+{
+	int ret;
+	struct v2m_data *v2m = NULL;
+
+	*v = kzalloc(sizeof(struct v2m_data), GFP_KERNEL);
+	if (!*v) {
+		pr_err("Failed to allocate struct v2m_data.\n");
+		return -ENOMEM;
+	}
+
+	v2m = *v;
+	v2m->gic = gic;
+	v2m->msi_chip.owner = THIS_MODULE;
+	v2m->msi_chip.of_node = node;
+	v2m->msi_chip.setup_irq = gicv2m_setup_msi_irq;
+	v2m->msi_chip.teardown_irq = gicv2m_teardown_msi_irq;
+	ret = of_address_to_resource(node, 0, &v2m->res);
+	if (ret) {
+		pr_err("Failed to allocate v2m resource.\n");
+		goto err_out;
+	}
+
+	v2m->base = ioremap(v2m->res.start, resource_size(&v2m->res));
+	if (!v2m->base) {
+		pr_err("Failed to map GICv2m resource\n");
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	ret = of_pci_msi_chip_add(&v2m->msi_chip);
+	if (ret) {
+		pr_info("Failed to add msi_chip.\n");
+		goto err_out;
+	}
+
+	if (!of_property_read_u32(node, "arm,msi-base-spi", &v2m->spi_start) &&
+	    !of_property_read_u32(node, "arm,msi-num-spi", &v2m->nr_spis)) {
+		pr_info("Overriding V2M MSI_TYPER (base:%u, num:%u)\n",
+			v2m->spi_start, v2m->nr_spis);
+	} else {
+		u32 typer = readl_relaxed(v2m->base + V2M_MSI_TYPER);
+
+		v2m->spi_start = V2M_MSI_TYPER_BASE_SPI(typer);
+		v2m->nr_spis = V2M_MSI_TYPER_NUM_SPI(typer);
+	}
+
+	if (!is_msi_spi_valid(v2m->spi_start, v2m->nr_spis)) {
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	v2m->bm = kzalloc(sizeof(long) * BITS_TO_LONGS(v2m->nr_spis),
+			  GFP_KERNEL);
+	if (!v2m->bm) {
+		pr_err("Failed to allocate MSI bitmap\n");
+		ret = -ENOMEM;
+		goto err_out;
+	}
+
+	spin_lock_init(&v2m->msi_cnt_lock);
+
+	pr_info("Node %s: range[%#lx:%#lx], SPI[%d:%d]\n", node->name,
+		(unsigned long)v2m->res.start, (unsigned long)v2m->res.end,
+		v2m->spi_start, (v2m->spi_start + v2m->nr_spis));
+
+	return 0;
+err_out:
+	of_pci_msi_chip_remove(&v2m->msi_chip);
+	if (v2m->base)
+		iounmap(v2m->base);
+	kfree(v2m);
+	return ret;
+}
+
+int __init gicv2m_of_init(struct device_node *node,
+			  struct gic_chip_data *gic,
+			  struct irq_chip *v2m_chip)
+{
+	int ret = 0;
+	struct v2m_data *v2m;
+	struct device_node *child = NULL;
+
+	INIT_LIST_HEAD(&gic->v2m_list);
+
+	v2m_chip->irq_mask = gicv2m_mask_irq;
+	v2m_chip->irq_unmask = gicv2m_unmask_irq;
+
+	for (;;) {
+		child = of_get_next_child(node, child);
+		if (!child)
+			break;
+
+		if (!of_device_is_compatible(child, "arm,gic-v2m-frame"))
+			continue;
+
+		if (!of_find_property(child, "msi-controller", NULL))
+			continue;
+
+		ret = gicv2m_init_one(child, &v2m, gic);
+		if (ret) {
+			of_node_put(node);
+			break;
+		}
+
+		list_add_tail(&v2m->list, &gic->v2m_list);
+	}
+
+	if (ret && list_empty(&gic->v2m_list)) {
+		pr_warn("Warning: Failed to enable GICv2m support.\n");
+		return -EINVAL;
+	}
+
+	return ret;
+}
diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index 4b959e6..9f8e1e0 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -46,30 +46,9 @@ 
 #include <asm/smp_plat.h>
 
 #include "irq-gic-common.h"
+#include "irq-gic.h"
 #include "irqchip.h"
 
-union gic_base {
-	void __iomem *common_base;
-	void __percpu * __iomem *percpu_base;
-};
-
-struct gic_chip_data {
-	union gic_base dist_base;
-	union gic_base cpu_base;
-#ifdef CONFIG_CPU_PM
-	u32 saved_spi_enable[DIV_ROUND_UP(1020, 32)];
-	u32 saved_spi_conf[DIV_ROUND_UP(1020, 16)];
-	u32 saved_spi_target[DIV_ROUND_UP(1020, 4)];
-	u32 __percpu *saved_ppi_enable;
-	u32 __percpu *saved_ppi_conf;
-#endif
-	struct irq_domain *domain;
-	unsigned int gic_irqs;
-#ifdef CONFIG_GIC_NON_BANKED
-	void __iomem *(*get_base)(union gic_base *);
-#endif
-};
-
 static DEFINE_RAW_SPINLOCK(irq_controller_lock);
 
 /*
@@ -131,15 +110,36 @@  static inline void gic_set_base_accessor(struct gic_chip_data *data,
 #define gic_set_base_accessor(d, f)
 #endif
 
+static inline
+struct gic_chip_data *irq_data_get_gic_chip_data(struct irq_data *d)
+{
+	struct gic_chip_data *gic_data;
+	struct msi_chip *mchip;
+	struct v2m_data *v2mdat;
+
+	/*
+	 * For MSI, irq_data.chip_data points to struct msi_chip.
+	 * For non-MSI, irq_data.chip_data points to struct gic_chip_data.
+	 */
+	if (d->msi_desc) {
+		mchip = irq_data_get_irq_chip_data(d);
+		v2mdat = container_of(mchip, struct v2m_data, msi_chip);
+		gic_data = v2mdat->gic;
+	} else {
+		gic_data = irq_data_get_irq_chip_data(d);
+	}
+	return gic_data;
+}
+
 static inline void __iomem *gic_dist_base(struct irq_data *d)
 {
-	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
+	struct gic_chip_data *gic_data = irq_data_get_gic_chip_data(d);
 	return gic_data_dist_base(gic_data);
 }
 
 static inline void __iomem *gic_cpu_base(struct irq_data *d)
 {
-	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
+	struct gic_chip_data *gic_data = irq_data_get_gic_chip_data(d);
 	return gic_data_cpu_base(gic_data);
 }
 
@@ -151,7 +151,7 @@  static inline unsigned int gic_irq(struct irq_data *d)
 /*
  * Routines to acknowledge, disable and enable interrupts
  */
-static void gic_mask_irq(struct irq_data *d)
+void gic_mask_irq(struct irq_data *d)
 {
 	u32 mask = 1 << (gic_irq(d) % 32);
 
@@ -162,7 +162,7 @@  static void gic_mask_irq(struct irq_data *d)
 	raw_spin_unlock(&irq_controller_lock);
 }
 
-static void gic_unmask_irq(struct irq_data *d)
+void gic_unmask_irq(struct irq_data *d)
 {
 	u32 mask = 1 << (gic_irq(d) % 32);
 
@@ -325,6 +325,15 @@  static struct irq_chip gic_chip = {
 	.irq_set_wake		= gic_set_wake,
 };
 
+static struct irq_chip v2m_chip = {
+	.name			= "GICv2m",
+	.irq_eoi		= gic_eoi_irq,
+	.irq_set_type		= gic_set_type,
+#ifdef CONFIG_SMP
+	.irq_set_affinity	= gic_set_affinity,
+#endif
+};
+
 void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
 {
 	if (gic_nr >= MAX_GIC_NR)
@@ -767,19 +776,29 @@  void __init gic_init_physaddr(struct device_node *node)
 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
 				irq_hw_number_t hw)
 {
+	struct gic_chip_data *gic = d->host_data;
+
+	irq_set_chip_data(irq, gic);
+
 	if (hw < 32) {
+		/* PPIs */
 		irq_set_percpu_devid(irq);
 		irq_set_chip_and_handler(irq, &gic_chip,
 					 handle_percpu_devid_irq);
 		set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
 	} else {
-		irq_set_chip_and_handler(irq, &gic_chip,
-					 handle_fasteoi_irq);
+		/* SPIs */
 		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
 
-		gic_routable_irq_domain_ops->map(d, irq, hw);
+		if (!gicv2m_check_msi_range(gic, hw)) {
+			irq_set_chip_and_handler(irq, &gic_chip,
+						 handle_fasteoi_irq);
+			gic_routable_irq_domain_ops->map(d, irq, hw);
+		} else {
+			irq_set_chip_and_handler(irq, &v2m_chip,
+					 handle_fasteoi_irq);
+		}
 	}
-	irq_set_chip_data(irq, d->host_data);
 	return 0;
 }
 
@@ -1010,6 +1029,9 @@  gic_of_init(struct device_node *node, struct device_node *parent)
 	if (of_property_read_u32(node, "cpu-offset", &percpu_offset))
 		percpu_offset = 0;
 
+	if (IS_ENABLED(CONFIG_ARM_GIC_V2M))
+		gicv2m_of_init(node, &gic_data[gic_cnt], &v2m_chip);
+
 	gic_init_bases(gic_cnt, -1, dist_base, cpu_base, percpu_offset, node);
 	if (!gic_cnt)
 		gic_init_physaddr(node);
diff --git a/drivers/irqchip/irq-gic.h b/drivers/irqchip/irq-gic.h
new file mode 100644
index 0000000..3021665
--- /dev/null
+++ b/drivers/irqchip/irq-gic.h
@@ -0,0 +1,54 @@ 
+#ifndef _IRQ_GIC_H_
+#define _IRQ_GIC_H_
+
+#include <linux/msi.h>
+#include <linux/pci.h>
+
+union gic_base {
+	void __iomem *common_base;
+	void __percpu * __iomem *percpu_base;
+};
+
+struct gic_chip_data;
+
+struct v2m_data {
+#ifdef CONFIG_ARM_GIC_V2M
+	struct list_head list;
+	spinlock_t msi_cnt_lock;
+	struct msi_chip msi_chip;
+	struct resource res;      /* GICv2m resource */
+	void __iomem *base;       /* GICv2m virt address */
+	unsigned int spi_start;   /* The SPI number that MSIs start */
+	unsigned int nr_spis;     /* The number of SPIs for MSIs */
+	unsigned long *bm;        /* MSI vector bitmap */
+	struct gic_chip_data *gic;
+#endif
+};
+
+struct gic_chip_data {
+	union gic_base dist_base;
+	union gic_base cpu_base;
+#ifdef CONFIG_CPU_PM
+	u32 saved_spi_enable[DIV_ROUND_UP(1020, 32)];
+	u32 saved_spi_conf[DIV_ROUND_UP(1020, 16)];
+	u32 saved_spi_target[DIV_ROUND_UP(1020, 4)];
+	u32 __percpu *saved_ppi_enable;
+	u32 __percpu *saved_ppi_conf;
+#endif
+	struct irq_domain *domain;
+	unsigned int gic_irqs;
+#ifdef CONFIG_GIC_NON_BANKED
+	void __iomem *(*get_base)(union gic_base *);
+#endif
+#ifdef CONFIG_ARM_GIC_V2M
+	struct list_head v2m_list;
+#endif
+};
+
+void gic_mask_irq(struct irq_data *d);
+void gic_unmask_irq(struct irq_data *d);
+int gicv2m_of_init(struct device_node *node, struct gic_chip_data *gic,
+		   struct irq_chip *v2m_chip) __init;
+bool gicv2m_check_msi_range(struct gic_chip_data *gic, irq_hw_number_t hw);
+
+#endif /* _IRQ_GIC_H_ */